Jersey is the open source (under dual CDDL+GPL license), production quality, JAX-RS (JSR 311) Reference Implementation for building RESTful Web services. But, it is also more than the Reference Implementation. Jersey provides an API so that developers may extend Jersey to suite their needs. The governance policy is the same as the GlassFish project.
Where possible, creating Web applications — including Ajax-based applications — in a RESTful way avoids a large class of bugs. However, a pitfall of REST (REpresentational State Transfer) is sending duplicate data across similar XMLHttpRequests. This tip shows how the moderate use of session cookies can maintain just enough server-side state to significantly reduce client-server traffic, while still allowing fallback to cookie-free operation.
Apache CXF is an open source services framework. CXF helps you build and develop services using frontend programming APIs, like JAX-WS. These services can speak a variety of protocols such as SOAP, XML/HTTP, RESTful HTTP, or CORBA and work over a variety of transports such as HTTP, JMS or JBI.